In the prior art, various environment detection systems for motor vehicles are known which support the driver in driving the vehicle. DE 10 2004 057 060 A1 discloses in this context a driver assistance device for detecting obstacles in its own traffic lane by means of environment sensors such as radar, lidar or camera. By comparing the relative speed to the obstacle with its own vehicle speed, it is possible to determine whether it is a stationary obstacle or a vehicle approaching its own vehicle. If necessary, the device disclosed intervenes in the steering, the braking, the engine or the transmission.
DE 10 2007 042 792 A1 describes a method for the environment monitoring of a vehicle which, apart from environment sensors, also uses vehicle-to-vehicle communication means. In order to be able to respond more quickly to a hazard situation, data of vehicles which are not recognizable to the environment sensors are also detected via the vehicle-to-vehicle communication means. For example, a beginning braking process of the vehicle in front of the preceding vehicle can thus be detected although this vehicle is hidden by the preceding vehicle and can thus not be detected by the environment sensors. His own vehicle can thus be decelerated already before the environment sensors detect a braking process of the preceding vehicle.
By this means, it is possible to reduce the hazard of a collision accident in the case of sudden braking of the preceding vehicle, e.g. in a line of traffic.
In DE 10 2007 039 110 A1, a driver assistance system is also defined which increases the attention of the driver of a vehicle by means of an advance-warning stimulus for a warning signal possibly following. If an environment sensor detects a critical situation, an advance-warning stimulus which is only insignificantly above the perception threshold of the driver is output even before the environmental situation could be reliably detected by the driver. The advance-warning stimulus is designed in such a manner that the driver does not undertake any steering or braking action on the basis of this stimulus alone. As soon as the environmental situation has been detected reliably, a warning signal is output to the driver, if necessary. Since the attention of the driver has already been enhanced by the advance-warning stimulus, he can react more quickly to the warning signal.
The disadvantage of these devices and methods known from the prior art consists in the fact that, due to the existing high safety risks, they intervene in a vehicle control system or output a warning to the driver only when an environmental situation could be validated reliably. As a result, a period of time which is important and required for avoiding an accident or at least reducing an accident may be lost. Even if, in the case of a suspicion of a hazard situation, an advance-warning stimulus is output immediately to the driver, a possibly decisive period of time passes unused until a full warning is output. The advance-warning stimulus only reduces the period of time needed by the driver for responding to the full warning. It is especially in the case of the systems gaining more and more popularity, which carry out a completely autonomous control intervention, that the response time of the driver no longer plays a role, in any case, however.
It is the object of the present invention, therefore, for avoiding a reaction delay time, in the case of detection of an environmental situation exhibiting a risk of collision, without validation of the environmental situation, to immediately perform an intervention in the vehicle control without creating a hazard for the surrounding traffic, as a result.
According to the invention, this object is achieved by the method for reducing a reaction delay time of a vehicle safety control device as and system as described herein.